Defensive shifts are on the rise in baseball, and data driven teams are at the forefront of the increasing use of the shift. Since the Astros are oriented toward sabermetrics, we shouldn't be surprised that the Astros exhibited the most significant increase in the use of shifts and were among the league leaders in using defensive shifts.
Jeff Zimmerman's recent Hardball Times article provides data on BABIP (batting average on balls in play) results for defensive shifts in 2013. I have analyzed some of the summary data he presents. (Note that some of the data I use is slightly different from the tables in his article, because he subsequently corrected errors in the underlying data spreadsheets.)
The team data below is based on shifts for balls in play (i.e., it doesn't include all instances of putting on the shift---only when the ball was put in play). The table shows the top ten ML teams in putting on the shift when a ball was put in play. BABIP-shift and BABIP-no shift reflect the BABIP when the shift was on and when it wasn't. Difference reflects the BABIP points difference between the team's overall BABIP and BABIP-shift.
The Astros had the fifth highest number of major defensive shifts. The Astros may have an above average overall pitching BABIP, but the shift appears to be producing a beneficial effect, slicing five points of BABIP compared to situations when the shift is not used. Only two of the teams, above, (Yankees and Cubs) produced worse results with the shift than without it. I would note that Zimmerman's data base shows a higher pitching BABIP for the Astros than either fangraphs or baseball-reference; it's unclear whether this is due to a different calculation of BABIP or the sample of batters used by Zimmerman. This discrepancy is not limited to the Astros.
In the image, below, Jose Altuve, from his shift position in short RF, catches a "fliner" hit by Raul Ibanez.
Because the data is not very detailed, my analysis is somewhat limited. But an examination of the relationships in the data for all 30 teams appears to confirm that the shift practice suppresses BABIP.
- On average, shifts produced a BABIP 1.5 points below the overall team BABIP. This decrease in BABIP has a 0.29 correlation with overall BABIP.
- The number of shifts used by a team has an inverse correlation (r= -.49) with team BABIP, suggesting that an increased used of shifts is associated with lower overall BABIP. The R-squared indicates that the number of shifts explains 22% of the variation in team BABIP. This is a surprisingly high percentage, considering that, on average, shifts are applied to only 5% of balls in play. Perhaps shifts are associated with other defensive or pitching relationships.
- BABIP-shift has a 0.55 correlation with overall BABIP. This isn't all that surprising since BABIP-shift is a component of overall BABIP.
- I wondered whether the lower BABIP-shift could be due to a selection bias caused because players subjected to shifts are likely to be low BABIP hitters. However, this doesn't seem to be the case. For all hitters who put a ball in play at least 90 times against the shift, the average BABIP--including the shift--is above average (.298 vs..294 MLB average). Without the shift, these hitters have a .320 BABIP. To the extent that a selection bias exists, it suggests that the reductions in team BABIP caused by the shift is understated.
The Astros' acquisition of groundball pitchers in the off-season, along with existing groundballers like Keuchel and Cosart, has turned fans' focus to the team's defense. The shift strategies could provide a means for improving defensive results without major changes to the existing pool of infielders. Effective use of defensive shifts can be used to minimize weaknesses of particular defenders, while also taking advantage of the strengths of better defenders. In theory, shifts can mitigate the limited range of defenders, which could allow a team to produce better results from personnel who lack plus fielding range. For example, Jose Altuve's height may create some fielding weaknesses, but the shifts put him in a position to do what he does well, such as reliably catching the ball and making good decisions on throws. Since shifts are most prevalent against LHBs, in most cases they will put the Astros' best fielder, Matt Dominguez, in a position to make more plays.
Astros' second basemen made the 7th most out of zone plays in 2013. Astros' third basemen made the 8th most out of zone plays. On an individual basis, Altuve and Dominguez made the 4th most out of zone plays among qualified second basemen and third basemen, respectively. This reflects the fact that the Astros' shifts put them in a position to make a large number of plays outside of the normal zone for their position. In addition, this implies that advanced metrics, like UZR, may not be adequate measures of their defensive contributions, since UZR excludes out of zone plays.
Since the Astros' data miners have had a full off-season to evaluate their shift strategies, it will be interesting to find out what changes they may make in 2014. Although the Astros gained some benefits from their shifts--as shown by the Zimmerman data--several of the other high Shift teams achieved significantly larger BABIP reductions. For example, the Orioles, Rays, and Red Sox have 15, 36, and 41 point differentials between BABIP-shift and BABIP. Given the volatility of BABIP, it's possible than luck accounts for some of the differences. (Also, since those three teams reside in the AL East, maybe there are more opportunities for shift strategies against particular hitters.) However, it's also plausible that those teams are more effective at designing and executing defensive shifts. My guess is that there is room for more improvement in the Astros' defensive shifting.
The Pirates' front office believes that the data driven defensive positioning played a major role in the improvement of the team's pitching results. Reportedly, the Pirates plan to take the same approach to outfield shifts in 2014. Although this seems like a potentially risky strategy, it also may carry high rewards. (The consequences of a fly ball or line drive falling safely in the outfield is greater, because hits for extra bases are more likely.) Would the Astros take a similar view?
Josh Hamilton hits a weak grounder in the direction of a shifted Altuve.
The criticism levied last year by Lucas Harrell against the Astros' shifting underscores the need to communicate and "sell" the strategy to pitchers. In contrast to Harrell's criticism, as indicated in this interview
, Red Sox sinkerballer Burke Badenhop has embraced defensive shifting as a key to his success, frankly recounting the different approaches he has experienced with saber- and non-saber oriented organizations. Badenhop discusses one of the principles of shifting:
"One thing I've learned in Tampa that they've reiterated here is that you want to catch line drives. We don't want guys to be kind of where they hit it," he explained. "We want to be exactly where they hit it the hardest, because then if they deviate from there, it's a little weaker contact. Weaker contact does what? It gives the infielder more time to get to those balls.
"It's all probability. It's all probability. If this guy hits the ball on the screws, what's the probability that you'll get it? You've got to be right there pretty much, or within arm's length. If this guy chops the ball then the probability of you getting the ball there is great."
Bud Norris, on the other hand, may have left for Baltimore, but he continues to be critical of the Astros defensive shifts. In a quote for a mlb.com article
on the defensive shift trend, Norris states his belief that the Astros were more interested in using shifts to build a data base than for putting fielders in a position to get outs. Although I have trouble buying that contention, I think it illustrates that the Astros may need to communicate more clearly with their pitching staff about the basis for shifting. In the end, the success of shifts will depend on the ability and willingness of pitchers to command their pitches consistent with the shifting objective.
The St. Louis Cardinals were not a shift oriented team, reportedly out of concern about the possible reaction of their pitchers.The mlb.com article (linked above) says that the Cardinals plan to transition to a greater emphasis on shifts by employing them in the minor leagues, so that young pitchers will be more comfortable with the practice. Do the Astros plan to utilize defensive shifting strategies in their farm system? I don't know, but it makes some sense. And that's a segue into a question for Hooks' fans.
Question for Corpus Christi Hooks fans
For those of you who watch the Hooks, do the Astros employ defensive shift strategies? And, how good was the Hooks' defense in 2013?
The Hooks pitching staff comprised 5 of the top 10 Texas League pitchers in BABIP (>70 IP). Look at the BABIPs below.
Hooks' Pitcher/ BABIP/ League Rank
Buchanan/ .252/ 2
Martinez/ .259/ 6
Queveda/ .269/ 9
Doran/ .273/ 10
Although it is more difficult to evaluate the implications of BABIP in the minor leagues, we normally question whether pitchers with low BABIP benefited from batted ball luck. However, that
many pitchers on the same team with very low BABIP seems more than coincidental. It reminds me of some of the Rays' pitching staffs in the past (examples here
, and here
) which exhibited very low BABIP. Many attributed this to the Rays' defensive prowess and the aggressive use of shifts.
Tropeano and Alaniz are the only Hooks pitchers who posted at least 70 innings with a high BABIP. So, I throw this question out to those who watched the Hooks' games. Is there a defense-related explanation for so many Hooks' pitchers with low BABIP?